Why they are no timelines in macros ?

Just today i’v found out that macro has delays and even local variables, which is super awesome ! ( like the functions old style variables from versions before 4.2 ).
So i put them together and i manage to make a basic lineal float time line (in this on ei have assigned the delay to 1 sec instead of deltaTime so it will be noticeable):

So if this can be done, why can’t timelines?